It works for up to 36 hours. Recent heart or blood vessel problems. You’ll also need to fill out a medical questionnaire with answers about your medical history, current medications, and lifestyle habits. Alpha-blockers are sometimes prescribed for prostate problems or high blood pressure. The four main medicines taken by mouth for erectile dysfunction are: Avanafil Stendra.According to price-comparison site , generic Revatio will cost you as little as $ per pill, depending on where you fill your prescription. That’s compared with . CHOOSE BRAND-NAME VIAGRA The original little blue pill prescribed by doctors for over 20 years Clinically proven to treat men with erectile dysfunction (ED) Ongoing . AdMany Americans pay far too much for their prescriptions. We’re here to help. Compare pharmacy prices in your area, get the free coupon, & see how much you can save!””GoodRx can help you save, whether you have insurance or not.”” – Patch.